Our previous research about possible quality improvements in Extreme Programming (XP) led us to
a conclusion that XP supports many good engineering practices but there is still place for refinements. Our
proposal was to add dedicated Quality Assurance (QA) measures, which should be sufficiently effective and
at the same time simpler enough in the context of XP. This paper intends to analyze the possibilities for an
effective way for applying approved quality assurance practices to XP. The last should not affect negatively to
the process and in the meantime must lead to better quality assurance. We aim to make changes to XP that
even if would slow down a bit the development process, will make it more suitable for widest range of projects
including large and very large projects as well as life critical and highly reliable systems.